Question on headstock taper

[Frederick Skelly]

Good morning folks,
I'm trying to determine what the correct size Morse Taper is for the Headstock of my HF34706.

As I understand it, my lathe is a close relative of the JET JWL1236. The HF website only specifies that the TAILSTOCK taper is MT2. An old ad I found for the JET says both headstock and tailstock are MT2. I don't know if I can count on them being exactly the same in this regard or not.

The drive center is 2 19/32" long, excluding a cone/tang at the end. According to one reference I have, that might mean it's an MT1. The tailstock live center is shorter than the 3 1/8" long that my reference shows for MT2, but I'm guessing that the rest of the length is inside the bearing of the live center.

Both the drive center and the live center seem to be interchangeable between headstock and tailstock, but they don't engage/stop at exactly the same depth - which makes me suspicious.

I don't want to jam my headstock/tailstock. Can anyone suggest how to figure this out?

Once again, thanks for putting up with all the newbie questions. I really did try to figure this one out myself.

Fred

[Brice Rogers]

If you go to Harbor Fright :eek: on line, you can download their manual. In the first few pages, it specifies that both the headstock and tailstock are MT2. MT1 and MT2 are quite a bit different. You could not put an MT2 into a hole for an MT1 and if you tried the reverse, it would just loosely rattle around.

[Frederick Skelly]

Oh geez. :eek: (Big head slap.) I tried everything EXCEPT the obvious of looking for the HF manual online. I apologize Brice.

And thank you for the extra information, because I've (obviously!) never seen an MT1.

Thanks for straightening me out.

Fred

[John K Jordan]

...I've (obviously!) never seen an MT1.



This picture is of some taper drills I use. The three at the top are MT2. The three at the bottom are MT1.

In the middle is an adapter sleeve to let me use the MT1 drills in an MT2 socket.

Maybe this will give you an idea of the size difference.

345684

BTW, I use these drills on the wood lathe - much quicker, takes less space, and more precise than using a standard drill bit in a Jacob's chuck. A comparison:

345685 345686

You should see an MT3 - it's huge! My metal-cutting lathe uses MT3 in the headstock and MT2 in the tailstock.

JKJ

[Leo Van Der Loo]

A metal and wood lathe do not use the tang of the MT drills, like a drill press does,where it is used to prevent the twisting of the drill in the taper opening.

In the headstock of a lathe you should have a MT with a threaded opening,(a drawbar threads into it) this is also used to prevent twisting the MT in the spindle, especially if there is no pressure against it from the tailstock to keep it seated.

What I have noticed with some of the wood lathes, is that the MT openings length is shorter than the standard, it can even prevent a full length MT from seating especially if it has a tang on it.

Also in the tailstock a MT with a tang can/will prevent the use of the total movement of the tailstock ram and some times prevent the ejection of the MT in the tailstock.

I have a MT4 opening in my metal lathe spindle, and use sleeves to use MT2 or MT3 drills and accessories in it, here is a chart that gives the standard MT measurements and tapers per inch for them.

345689

[Frederick Skelly]

This picture is of some taper drills I use. The three at the top are MT2. The three at the bottom are MT1.

In the middle is an adapter sleeve to let me use the MT1 drills in an MT2 socket.

Maybe this will give you an idea of the size difference.

345684

BTW, I use these drills on the wood lathe - much quicker, takes less space, and more precise than using a standard drill bit in a Jacob's chuck. A comparison:

345685 345686

You should see an MT3 - it's huge! My metal-cutting lathe uses MT3 in the headstock and MT2 in the tailstock.

JKJ

Wow. There sure is a difference. Thank you for showing me that John!

[Frederick Skelly]

9
A metal and wood lathe do not use the tang of the MT drills, like a drill press does,where it is used to prevent the twisting of the drill in the taper opening.

In the headstock of a lathe you should have a MT with a threaded opening,(a drawbar threads into it) this is also used to prevent twisting the MT in the spindle, especially if there is no pressure against it from the tailstock to keep it seated.

What I have noticed with some of the wood lathes, is that the MT openings length is shorter than the standard, it can even prevent a full length MT from seating especially if it has a tang on it.

Also in the tailstock a MT with a tang can/will prevent the use of the total movement of the tailstock ram and some times prevent the ejection of the MT in the tailstock.

I have a MT4 opening in my metal lathe spindle, and use sleeves to use MT2 or MT3 drills and accessories in it, here is a chart that gives the standard MT measurements and tapers per inch for them.

345689

Thank you Leo! Much appreciated.

[John K Jordan]

A metal and wood lathe do not use the tang of the MT drills, like a drill press does,where it is used to prevent the twisting of the drill in the taper opening. ...

Fortunately the twisting forces when drilling wood are very small compared to drilling steel and twisting has not been a problem for me at the wood lathe. Of course, it is necessary to keep the taper absolutely clean and any dents, nicks, or scratches must be dressed. I buy hardened and ground adapters but the drill shanks are not hardened.

Where the length if a tang is a problem it can be shortened at the grinder.

Most of my drilling on the lathe is with the bit in the tailstock MT. When I use a drill bit as a jam chuck in the headstock I generally mount one in a Jacobs chuck and secure with a drawbar. A drawbar is also useful to hold thin wood spindles in the MT when the tailstock can't be used - I tap threads into the end grain.


JKJ